why get error "Type mismatch (arg. no. 1) (ptrs to signed/unsigned)"?

"As you just suggested,I changed the following code.
//unsigned int num

//older version
sprintf((char *)lcd_show_buf, "%4d", num);

//latest version
sprintf((char *)lcd_show_buf, "%4u", num);

I didn't find the ANSI integer promotion switch you said. I just find the latest version occupy more code space, 41177B to 41181B."

I didn't mean you should make num an int. The idea is this:

unsigned char num=5;

sprintf((char *)lcd_show_buf,"%4bu",num);

The above should produce the tightest code provided ANSI integer promotion is turned off. It will not work properly if it is turned on. By doing the above you can maintain num as a single byte variable *and* avoid it being converted to a 2 byte int during the call to sprintf(), hence less code.

Stefan

"As you just suggested,I changed the following code.
//unsigned int num

//older version
sprintf((char *)lcd_show_buf, "%4d", num);

//latest version
sprintf((char *)lcd_show_buf, "%4u", num);

I didn't find the ANSI integer promotion switch you said. I just find the latest version occupy more code space, 41177B to 41181B."

I didn't mean you should make num an int. The idea is this:

unsigned char num=5;

sprintf((char *)lcd_show_buf,"%4bu",num);

The above should produce the tightest code provided ANSI integer promotion is turned off. It will not work properly if it is turned on. By doing the above you can maintain num as a single byte variable *and* avoid it being converted to a 2 byte int during the call to sprintf(), hence less code.

Stefan